Energy — Paper 1 · A Level Biology 9700

39 The diagram represents loss of energy from a food chain to decomposers, transfer of energy to the next trophic level and energy loss through respiration. All figures are in kJ m–2 y–1. loss to total energy of respiratory loss decomposers trophic level 24 40 16 360 115 205 carnivore 3 600 1 188 herbivore 2 052 36 360 11 880 primary producers 20 880 What is illustrated by this diagram? A Carnivores lose more energy than herbivores. B Energy loss to decomposers is higher than respiratory loss. C Energy transfer between trophic levels is about 10 %. D The energy of the final trophic level is not used.

1 marks

Answer: C

This question in 9700/11 Oct/Nov 2006

40 The diagram shows the flow of energy through an ecosystem. Photosynthesis is the gross productivity. Producers lose some energy in respiration and the energy left is the net productivity. This can also be expressed as an equation: Net Productivity (NP) = Gross Productivity (GP) – Respiration (R) Some of the net productivity passes to herbivores. energy from sunlight photosynthesis 96 % producers gross productivity 4 % 2.25 % lost in respiration net productivity 1.75 % 1 % to decomposers 0.75 % primary consumers 0.275 % to 0.4 % lost in respiration decomposers 0.075 % secondary consumers 0.0685 % to 0.06 % lost in respiration decomposers Which calculation gives the proportion of net productivity passing to herbivores? 0.075 0.75 0.75 ( 0.75 +0.075 ) A B C D 1.75 4 1.75 1.75

1 marks

Answer: C

This question in 9700/11 Oct/Nov 2007

40 Of the prey consumed by the lion, into which box does the largest amount of energy go? B C energy used in growth, energy lost as repair and reproduction heat from A respiration energy lost in urine energy assimilated energy consumed energy consumed energy lost in faeces D

1 marks

Answer: C

This question in 9700/11 Oct/Nov 2008

38 The diagram shows a tropical ocean food chain with 10 % efficiency of energy transfer between trophic levels. herbivorous carnivorous phytoplankton small fish tuna zooplankton zooplankton Net primary production of phytoplankton is 1300 g m–3 yr –1. What is the net primary production per year for the carnivorous zooplankton and the tuna? net primary production of net primary production of tuna carnivorous zooplankton / g m–3 yr –1 / g m–3 yr–1 A 1.3 × 101 1.3 × 10–1 B 1.3 × 100 1.3 × 10–2 C 1.3 × 10–1 1.3 × 10–2 D 1.3 × 10–2 1.3 × 10–4

1 marks

Answer: A

This question in 9700/11 May/June 2010

38 The table shows the results of a field study of four species in a food chain in an area of woodland. energy value per number of biomass of one species unit mass individuals individual / arbitrary units / arbitrary units P 10 000 0.100 1.0 Q 5 10.000 2.0 R 500 0.002 1.8 S 3 300 000.000 0.5 Which is the correct pyramid of energy from these data? A B S R Q Q R P P S C D S R P P R Q Q S

1 marks

Answer: B

This question in 9700/11 Oct/Nov 2010

39 The diagram represents the flow of energy through a tropical rainforest ecosystem. respiration respiration respiration W X primary Y secondary Sun producers consumers consumers detritus Z decomposers Which set of figures identifies the percentage transfer of energy between the Sun, producers, consumers and decomposers? W X Y Z A 1 10 20 80 B 1 20 10 80 C 10 20 1 10 D 10 10 1 20

1 marks

Answer: A

This question in 9700/11 Oct/Nov 2010

2 The table shows the results of a field study of four species in a food chain in an area of woodland. number of biomass of one individual energy value per unit species individuals / arbitrary units mass / arbitrary units R 10 000 0.1 1.0 S 5 10.0 2.0 T 500 0.002 1.8 U 3 300 000.0 0.5 What is the energy flow in the food chain? from to A R T S U B S T R U C U R S T D U S T R

1 marks

Answer: C

This question in 9700/13 May/June 2012

3 The diagram shows the flow of energy through an ecosystem. Photosynthesis is the gross productivity. Producers lose some energy in respiration and the energy left is the net productivity. This can also be expressed as an equation: net productivity = gross productivity – respiration Some of the net productivity passes to herbivores. energy from sunlight photosynthesis 96 % producers gross productivity 4.0 % 2.3 % lost in respiration net productivity 1.8 % 1.0 % to decomposers 0.75 % primary consumers 0.28 % to 0.40 % lost in respiration decomposers 0.075 % secondary consumers 0.069 % to 0.060 % lost in respiration decomposers Which calculation gives the proportion of net productivity passing to herbivores? 0 . 075 0 . 75 0 . 75 ( 0 . 75 + 0 . 075 ) A B C D 1 . 8 1 . 8 4 . 0 1 . 8

1 marks

Answer: B

This question in 9700/13 May/June 2012

38 Which uses energy to produce its own food supply from inorganic compounds? A autotroph B consumer C heterotroph D saprotroph

1 marks

Answer: A

This question in 9700/13 May/June 2013

39 Two different ecosystems, X and Y, were compared. Both ecosystems are the same size and both have the same climate. The results of the comparison are shown in the table below. ecosystem X ecosystem Y greater number of trophic levels fewer number of trophic levels lower proportion of decomposers higher proportion of decomposers dominant producer is smaller dominant producer is larger and non-woody and woody has a smaller fluctuation has a larger fluctuation in environmental temperature in environmental temperature has less oxygen has more oxygen Using the information in the table, which statements are a valid suggestion concerning X and Y? 1 A greater percentage of primary producers are likely to be consumed by primary consumers in X than in Y. 2 X could be a marine aquatic ecosystem and Y could be a terrestrial ecosystem. 3 Energy losses between trophic levels are likely to be lower for X than for Y. 4 There is likely to be a higher rate of photosynthesis and production of organic matter in X than in Y. A 2 and 4 only B 1, 2 and 3 only C 1, 3 and 4 only D 1, 2, 3 and 4

1 marks

Answer: D

This question in 9700/13 May/June 2013

39 An insect consumes 180 J of plant material. Of this, 95 J of energy is passed out in the insect’s faeces and 58 J is used for respiration. Which percentage of the energy, in the original plant material taken in by the insect, is converted into biomass? A 10 % B 15 % C 32 % D 47 %

1 marks

Answer: B

This question in 9700/11 Oct/Nov 2013

38 A total of 3 × 106 kJ m–2 yr–1 is available from the producers in an ecosystem. In theory, how much of this energy would be available to tertiary consumers? A 3 × 104 kJ m–2 yr–1 B 3 × 103 kJ m–2 yr–1 C 3 × 102 kJ m–2 yr–1 D 3 × 101 kJ m–2 yr–1

1 marks

Answer: B

This question in 9700/13 May/June 2014

39 In a food chain, which link involves the least efficient energy transfer? A Bull fishes feed on small crustacea. B Herons feed on bull fishes. C Mangrove plants trap sunlight during photosynthesis. D Small crustacea feed on dead mangrove leaves.

1 marks

Answer: C

This question in 9700/13 May/June 2014

38 The diagram shows the flow of energy between organisms in an ecosystem. 1 2 3 4 Which correctly identifies each organism in the ecosystem? 1 2 3 4 A primary decomposers secondary producers consumers consumers B primary secondary producers decomposers consumers consumers C secondary decomposers producers primary consumers consumers D secondary primary decomposers producers consumers consumers

1 marks

Answer: C

This question in 9700/11 Oct/Nov 2014

39 In a freshwater food chain, which involves the least efficient energy transfer? A Large fishes feed on the small fishes. B Small fishes feed on the water fleas. C Unicellular algae trap sunlight. D Water fleas feed on the unicellular algae.

1 marks

Answer: C

This question in 9700/11 Oct/Nov 2014

39 Which stage of energy transfer has the lowest efficiency? A sunlight → producer B producer → primary consumer C primary consumer → secondary consumer D secondary consumer → tertiary consumer

1 marks

Answer: A

This question in 9700/12 Oct/Nov 2014

40 The diagram shows a simplified nitrogen cycle. During which stage does decomposition take place? nitrogen in atmosphere A plant animal proteins proteins B ammonium compounds nitrites nitrates C D

1 marks

Answer: B

This question in 9700/12 Oct/Nov 2014

40 In a food chain, which link involves the least efficient energy transfer? A Corn traps sunlight during photosynthesis. B Mice eat the grain from corn. C Mongooses feed on snakes. D Snakes feed on mice.

1 marks

Answer: A

This question in 9700/13 Oct/Nov 2014

39 In an ecosystem, at which stage is most energy lost? A sunlight → trophic level 1 B trophic level 1 → trophic level 2 C trophic level 2 → trophic level 3 D trophic level 3 → trophic level 4

1 marks

Answer: A

This question in 9700/11 May/June 2015

38 At which stage of a food chain in a tropical grassland is the energy transfer least efficient? A B C sun producer primary secondary consumer consumer D decomposer

1 marks

Answer: A

This question in 9700/12 May/June 2015

40 Of the prey consumed by the lion, into which box does the largest amount of energy go? B C energy used in growth, energy lost as repair and reproduction heat from A respiration energy lost in urine energy assimilated energy consumed energy consumed energy lost in faeces D

1 marks

Answer: C

This question in 9700/12 May/June 2015

6 Which of these processes will require ATP? 1 transport of water in the xylem 2 semi-conservative replication of DNA 3 facilitated diffusion of amino acids into the cell A 1, 2 and 3 B 1 and 2 only C 2 and 3 only D 2 only

1 marks

Answer: D

This question in 9700/12 Feb/March 2018

19 Companion cells use ATP to move hydrogen ions out of the cell and co-transporter proteins to allow hydrogen ions to return with sucrose molecules. Which two processes are involved in this movement? A active transport and diffusion B active transport and facilitated diffusion C exocytosis and diffusion D exocytosis and facilitated diffusion

1 marks

Answer: B

This question in 9700/12 Feb/March 2018

24 The diagram represents a molecule of ATP. P Q R What are the components of ATP labelled P, Q and R? P Q R A adenine deoxyribose phosphates B adenosine pentose a phosphate group C adenosine ribose phosphorus D purine pentose phosphates

1 marks

Answer: D

This question in 9700/12 Feb/March 2018

15 Which of these features increase the efficiency of ion uptake by a root hair cell? 1 many mitochondria in the cell 2 high concentration of ions in the vacuole 3 protein carriers in the cell surface membrane A 1, 2 and 3 B 1 and 3 only C 1 only D 2 and 3 only

1 marks

Answer: B

This question in 9700/11 May/June 2018

17 Which processes use energy in the form of ATP? 1 endocytosis 2 exocytosis 3 facilitated diffusion A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

1 marks

Answer: B

This question in 9700/13 May/June 2018

24 What occurs during each of DNA replication and transcription and translation? 1 ATP provides energy. 2 Condensation reactions occur to form a polymer. 3 Hydrogen bonds form between purine and pyrimidine bases. A 1, 2 and 3 B 1 and 2 only C 2 only D 3 only

1 marks

Answer: A

This question in 9700/13 May/June 2018

24 What is the common component of the three molecules RNA, DNA, and ATP? A adenosine B hydrogen bonds C phosphate D ribose

1 marks

Answer: C

This question in 9700/12 Oct/Nov 2018

5 Which statements about ATP are correct? 1 It is produced in mitochondria only. 2 It can be hydrolysed to form ADP. 3 It contains deoxyribose. A 1 and 3 B 1 only C 2 and 3 D 2 only

1 marks

Answer: D

This question in 9700/13 May/June 2019

5 Which statements about ATP are correct? 1 It is produced in chloroplasts. 2 It is used during protein synthesis. 3 It contains deoxyribose. 4 It is used in facilitated diffusion. 5 It is used to load sucrose into companion cells. A 1, 2 and 5 B 1, 3 and 5 C 2, 3, 4 and 5 D 2 and 4 only

1 marks

Answer: A

This question in 9700/13 Oct/Nov 2020

6 Which row shows correct features of ATP? carbohydrate site of production of ATP in ATP A deoxyribose mitochondria and chloroplasts B pentose mitochondria and chloroplasts C hexose chloroplasts only D ribose mitochondria only

1 marks

Answer: B

This question in 9700/13 Oct/Nov 2021

21 Which statement describes the structure of ATP? A It is a DNA nucleotide with two extra phosphates. B It is a DNA nucleotide with three extra phosphates. C It is an RNA nucleotide with two extra phosphates. D It is an RNA nucleotide with three extra phosphates.

1 marks

Answer: C

This question in 9700/12 May/June 2022

4 ATP molecules are synthesised in mitochondria. Which sugar is found in these ATP molecules? A deoxyribose B fructose C glucose D pentose

1 marks

Answer: D

This question in 9700/13 May/June 2022

15 Which processes use energy in the form of ATP? 1 endocytosis 2 exocytosis 3 facilitated diffusion A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

1 marks

Answer: B

This question in 9700/13 May/June 2022